JP2017133526A - Motor drive unit for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor drive unit A for a vehicle which dispenses with an electromagnetic motor, a control device or the like by using an oil pump 42 to be operated by using a reduction gear drive force, can be saved in a space and reduced in cost, and can use an injection device to widely feed oil to a gear-meshing part, a bearing part or the like at high liquid pressure and high injection speed or by spraying a lubricant in a spray state.SOLUTION: A relief valve 43c is arranged in an oil passage 42b between an oil pump 42 and an injection device (or a discharge nozzle 42c), an electric motor 1 is rotated at a high speed by maintaining constant the hydraulic pressure of the discharge nozzle 42c to the injection device, and thus, even if a discharge amount of the oil pump 42 largely exceeds an injection pressure which is necessary for the injection device of the oil pump 42, injection at high hydraulic pressure can be prevented and damage of the injection device can be protected.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a vehicle motor drive device, and more particularly to a lubricating structure of a vehicle motor drive device for an electric vehicle.

  In a vehicle motor drive device that uses an electric motor as a drive source and decelerates the rotation of the electric motor by a speed reducer to rotate a drive wheel, the rotation of the output shaft of the speed reducer is applied to a hub wheel provided on the output shaft. In-wheel motor system that transmits and drives the drive wheel supported by the hub wheel, and the drive shaft is connected to the output shaft of the reducer through a joint, and the rotation of the drive shaft is transmitted to the hub wheel And there is an on-board system that drives the driving wheel.

  As a speed reducer for these vehicle motor drive devices, an input gear shaft that is rotated by the output torque of an electric motor, an output gear shaft that is output to a drive wheel, and an intermediate gear provided between the input gear shaft and the output gear shaft There is a gear drive reduction mechanism including a shaft, and the output torque of the electric motor is sequentially reduced to output a large output torque from the output gear shaft.

  Since the gear drive speed reduction mechanism of the vehicle motor drive device is driven at high rotation and high output, the gear drive speed reduction mechanism generally applies the rotational force of the speed reduction element (gear or pulley) for the purpose of lubrication and cooling. There are a splash system used and a pump system for forced circulation using a pump.

JP 2006-258274 A JP 2000-193071 A

  Among these pump-type lubrication oil supply structures, there are also a shaft center oil supply type and an injection type, and in the shaft center oil supply type, a hole for oil supply is provided in the gear shaft, or a tooth surface from the shaft center oil passage There is a very expensive factor in gear processing, such as the need to provide an oil passage.

  On the other hand, in the injection type, a structure as in Patent Document 1 has been proposed. This system uses an electromagnetic pump to supply lubricating oil to the speed reducer (mainly gears and bearings) by injecting the lubricating oil sucked from the suction port at the bottom of the tank so as to blow upward. It is.

  However, in the technique of Patent Document 1, an electromagnetic pump for supplying lubricating oil is separately required, and the pump needs to be installed inside or outside the housing, so that a compact design is difficult. Moreover, in order to provide an electromagnetic pump, it is necessary to provide a battery and a control device separately, which causes an increase in cost.

  Further, the method of installing at the bottom of the housing and blowing up the lubricating oil has a problem that if the surface of the lubricating oil covers the jet outlet, there is a possibility that the oil does not reach the location to be lubricated. When measures are taken to reduce the amount of oil filled, the lubricating oil at the bottom of the tank is agitated by agitation of gears and the like, and there is a possibility that the lubricating oil does not reach the suction port.

  In Patent Document 2, it is proposed to lubricate the meshing surface of the gear using an internal pump. The internal pump in the technology of this Patent Document 2 is presumed to drive the pump using the rotational force of the gear, but if the speed reducer does not reach a certain rotational speed, the injection pressure from the injection device There is a high possibility that it cannot be secured. Patent Document 2 describes problems such as the lubricating oil being repelled by the rotation of the gear if there is not enough injection pressure to lubricate the gear meshing surface, but the injection pressure is secured using an internal pump. No measures are taken for cases where this is not possible.

  Therefore, the present invention eliminates the need for an electromagnetic motor, a control device, etc. by using an internal pump that is driven by using a reduction gear driving force, and can save space and cost. It is an object of the present invention to supply oil to a part or the like by spraying lubricating oil in a high fluid pressure, injection speed, or spray state using an injection device so that it can be supplied over a wide range.

  In order to solve the above problems, the present invention includes an electric motor that generates a driving force, a reduction gear that decelerates and outputs the rotation of the electric motor with a plurality of gear shafts, a housing that houses the reduction gear, A lubricating oil tank provided in the housing and driven by the rotational power of one of the gear shafts of the plurality of stages, the lubricating oil is sucked from the lubricating oil tank, and the lubricating oil is used as a gear tooth surface of the speed reducer. In the vehicle motor drive device that includes an oil pump that is supplied to the vehicle via an injection device, and drives the wheels by the output of the speed reducer, the oil pump has an injection device that has a rotation speed lower than the maximum rotation speed of the electric motor. And a relief valve for preventing excessive hydraulic pressure is provided in the oil passage between the injection device and the oil pump.

  The oil relief port of the relief valve is provided on the upper part of the gear engaging surface of the upper stage of the plurality of gear shafts of the speed reducer, and the lubricant dripping from the exhaust port of the relief valve is applied to the gear engaging surface of the upper stage of the gear shaft. It is preferable to supply.

  A housing that houses two speed reducers in parallel in the left and right is provided in the center, two electric motors are provided on the left and right sides of the housing, and the two speed reducers provided in the left and right parallel to the housing of the central speed reducer A common oil pump may be provided.

  An oil pump injection device may be provided on the side surface of the housing that houses the reduction gear.

  A lubricating oil tank is provided at the bottom of the housing that houses the speed reducer, and the oil level of the lubricating oil tank is positioned below the gear tooth surface of the gears provided on the multiple-stage gear shafts constituting the speed reducer. It is preferable.

  In the vehicle motor drive device according to the present invention, the oil pump is set to obtain a hydraulic pressure necessary for the injection device at a rotational speed lower than the maximum rotational speed of the electric motor, and an oil passage between the injection device and the oil pump is provided. In addition, a relief valve for preventing excessive hydraulic pressure is provided.

  By providing a relief valve in the oil path between the oil pump and the injection device (discharge nozzle) and keeping the hydraulic pressure to the injection device of the discharge nozzle constant, the electric motor rotates at high speed, and the discharge amount of the oil pump Even when the injection pressure required for the injection device is significantly exceeded, it is possible to protect the injection device from being damaged such as injection or injection due to high hydraulic pressure.

  In addition, the relief valve operates at a high speed where the hydraulic pressure supplied to the discharge nozzle by the electric motor is excessive, so the oil outlet of the relief valve rotates at the highest speed among the gear shafts of the speed reducer. It is possible to effectively lubricate gears that rotate at high speed by providing lubricating oil dripping from the relief valve discharge port to the gear meshing surface of the upper gear shaft. .

  When a lubricating oil tank is provided at the bottom of the housing that houses the speed reducer, and the oil level of the lubricating oil tank is positioned below the tooth surfaces of the gears provided on the multiple-stage gear shafts constituting the speed reducer The stirring resistance of the speed reduction part can be reduced.

1 is a longitudinal front view of a vehicle motor drive device according to an embodiment of the present invention. It is a disassembled perspective view of the reduction gear part of embodiment of FIG. It is a schematic side view which shows an example of the lubricating oil tank provided in the bottom part of the reduction gear housing in embodiment of FIG. It is a schematic side view which shows the other example of the lubricating oil tank provided in the bottom part of the reduction gear housing in embodiment of FIG. It is an enlarged view of an oil pump. It is a graph which shows the relationship between the rotation speed of an oil pump, and lubricating oil discharge amount. It is a vertical front view of the motor drive unit for vehicles concerning other embodiments of this invention. It is a disassembled perspective view of the reduction gear part of embodiment of FIG. (A) shows the power transmission state of a one-way clutch, (b) is the schematic which shows the power interruption state of a one-way clutch. It is a vertical front view of the motor drive unit for vehicles concerning other embodiments of this invention. It is a vertical front view of the motor drive unit for vehicles concerning other embodiments of this invention. It is a vertical front view of the motor drive unit for vehicles concerning other embodiments of this invention. It is a disassembled perspective view of the reduction gear part of embodiment of FIG. 1 is a schematic plan view of an electric vehicle equipped with a vehicle motor drive device of the present invention.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
As shown in FIG. 14, an electric vehicle 81 equipped with a vehicle motor drive device A according to an embodiment of the present invention has a driving force applied to each of a chassis 82, a front wheel 83, a rear wheel 84, and left and right front wheels 83. Two vehicle motor drive devices A for transmitting

  FIG. 14 shows a front wheel drive vehicle in which vehicle motor drive devices A are mounted on the chassis 82 one by one on the left and right front wheels 83, and the drive force of each vehicle motor drive device A is intermediate between the constant velocity joint 86 and the middle. This is transmitted to the left and right front wheels 83 via a drive shaft comprising a shaft 88.

  As a mounting form of the vehicle motor drive device A, any of a rear wheel drive system and a four wheel drive system may be used in addition to the front wheel drive system shown in FIG.

  A vehicle motor drive device A according to the present invention shown in FIG. 1 includes an electric motor 1 and a speed reducer 2 that decelerates the rotation of the electric motor 1, and is mounted on the vehicle symmetrically with the back to back.

  The electric motor 1 and the speed reducer 2 are accommodated in a motor housing 3 and a speed reducer housing 4, respectively.

  The motor housing 3 includes a cylindrical motor housing body 3a whose outer surface is open, an outer wall 3b that closes the outer surface of the motor housing body 3a, and an inner wall that is separated from the speed reducer 2 inside the motor housing body 3a. 3c. The inner wall 3c of the motor housing body 3a is provided with an opening for drawing out the motor shaft 12a.

  As shown in FIG. 1, the electric motor 1 is a radial gap type in which a stator 11 is provided on the inner peripheral surface of the motor housing body 3 a and a rotor 12 is provided at an interval on the inner periphery of the stator 11. ing. Although not shown, an axial gap type electric motor 1 may be used.

  The rotor 12 has a motor shaft 12a at the center, and the motor shaft 12a is drawn out from the opening of the inner wall 3c of the motor housing body 3a to the speed reducer 2 side. A seal member 13 is provided between the opening of the motor housing body 3a and the motor shaft 12a.

  The motor shaft 12a is rotatably supported by rolling bearings 14a and 14b on the inner wall 3c and the outer wall 3b of the motor housing body 3a (FIG. 1).

  The reduction gear housing 4 that houses the reduction gear 2 includes a motor side housing 4a that is fixed to the motor housing body 3a and a side housing 4b that is fixed to the inner side surface of the motor side housing 4a. A flow path forming plate 4c for lubricating oil is fixed to.

  By fixing the side surface on the outboard side of the side housing 4b of the speed reducer housing 4 and the inner side wall 3c of the motor housing body 3a of the electric motor 1 by a plurality of bolts 29, the electric motor is mounted on the side of the speed reducer housing 4. 1 is fixedly arranged.

  A housing chamber 22 for housing the speed reducer 2 is provided in the motor side housing 4 a and the side housing 4 b of the speed reducer housing 4.

  As shown in FIG. 1, the speed reducer 2 includes an input shaft 23 having an input gear 23a to which power is transmitted from a motor shaft 12a, a large-diameter gear 24a that meshes with the input gear 23a, and a small-diameter gear 24b that meshes with an output gear 25a. Is a parallel shaft gear reducer provided with an intermediate shaft 24 having an output shaft and an output shaft 25 having an output gear 25a.

  Both ends of the input shaft 23 of the speed reducer 2 are rotatably supported via rolling bearings 28a and 28b by a boss portion 27a formed on the motor side housing 4a and a boss portion 27b formed on the side housing 4b.

  The end on the outboard side of the input shaft 23 is drawn outward from the opening provided in the motor side housing 4a, and a seal member 31 is provided between the opening and the outer end of the input shaft 23. The leakage of the lubricating oil sealed in the speed reducer 2 is prevented.

  The input shaft 23 has a hollow structure, and the motor shaft 12 a is inserted into the hollow input shaft 23. The input shaft 23 and the motor shaft 12a are splined.

  The intermediate shaft 24 is a stepped gear having a large-diameter gear 24a meshing with the input gear 23a and a small-diameter gear 24b meshing with the output gear 25a on the outer peripheral surface. Both ends of the intermediate shaft 24 are supported via rolling bearings 34a and 34b by a boss portion 32 formed on the motor side housing 4a and a boss portion 33 formed on the side housing 4b.

  The output shaft 25 has a large-diameter output gear 25a and is supported by rolling bearings 37a and 37b on a boss portion 35 formed on the motor side housing 4a and a boss portion 36 formed on the side housing 4b.

  The end portion on the outboard side of the output shaft 25 is pulled out of the reducer housing 4 from the opening formed in the motor side housing 4a, and is drawn on the outer peripheral surface of the end portion on the outboard side of the output shaft 25 that is pulled out. The outer ring member 15a of the constant velocity joint is splined.

  The constant velocity joint coupled to the output shaft 25 is connected to drive wheels (not shown) via a drive shaft (not shown).

  A seal member 39 is provided between an end on the outboard side of the output shaft 25 and an opening formed in the motor side housing 4a to prevent leakage of the lubricating oil sealed in the speed reducer 2.

  An oil pump 42 is provided on the inner side surface of the side housing 4 b of the speed reducer 2 by the rotation of the intermediate shaft 24 and the output shaft 25.

  As shown in FIG. 3 or 4, the reduction gear housing 4 of the reduction gear 2 is provided with a lubricating oil tank 41 at the bottom.

  In the lubricating oil tank 41 of FIG. 4, the oil surface of the lubricating oil tank 41 is a plurality of gear shafts constituting the speed reducer 2, that is, the input shaft 23, the intermediate shaft 24, and the output shaft 25. Among them, the large diameter gear 24 a provided on the intermediate shaft 24 is in a position where it is immersed in the lubricating oil in the lubricating oil tank 41.

  When the gears constituting the speed reducer 2 are immersed in the lubricating oil in the lubricating oil tank 41, the influence of the stirring resistance appears.

  For this reason, in the embodiment of FIG. 3, the position of the oil surface of the lubricating oil tank 41 provided at the bottom of the speed reducer housing 4 of the speed reducer 2 is set to a plurality of gear shafts constituting the speed reducer 2, that is, the input shaft 23. The influence of the stirring resistance is reduced by setting the gears provided on the intermediate shaft 24 and the output shaft 25 so as not to be immersed.

  The flow path forming plate 4c fixed to the inner surface of the side housing 4b of the speed reducer 2 includes an oil passage 42a from the lubricating oil tank 41 to the suction port of the oil pump 42, and a discharge port of the oil pump 42 to the speed reducer 2. An oil passage 42b reaching the discharge nozzle 42c provided on the upper surface of the reduction gear housing 4 is provided.

  As the discharge nozzle 42c, an injection device using an injector can be used, and the gears of the intermediate shaft 24 and the output shaft 25 can spray sprayed lubricating oil over a wide range.

  The oil pump 42 is set to obtain a hydraulic pressure necessary for the discharge nozzle 42c of the injection device at a rotation speed lower than the maximum rotation speed of the electric motor 1.

  For example, the discharge amount is set so that the oil pump 42 can pump the necessary hydraulic pressure from the discharge nozzle 42c at about 1/3 to 1/2 of the maximum rotation speed of the electric motor 1. That is, the oil pump 42 can apply a sufficient injection pressure to the discharge nozzle 42c at a low rotation.

  In the speed reducer 2 using a parallel shaft gear speed reducer, when the amount of oil supplied for lubrication and cooling is 10 l / min, the oil pump 42 can be supplied at 10000 rpm which is the maximum rotation speed of the electric motor 1. Instead of designing, in the present invention, as shown in the graph of FIG. 6, the oil pump 42 is designed so that the supplied oil amount of 10 l / min can be supplied at, for example, 5000 rpm which is half the maximum rotational speed of the electric motor 1. doing.

  If the oil pump 42 is designed as shown in FIG. 6, the hydraulic pressure supplied to the discharge nozzle 42 c becomes an excessive region at the maximum rotation speed of the electric motor 1.

  For this reason, in the present invention, the relief valve 43c is provided in the oil passage 42a between the discharge nozzle 42c and the oil pump 42 so as to reduce the hydraulic pressure in the excessive hydraulic pressure region and prevent the excessive hydraulic pressure from being applied to the discharge nozzle 42c. An excessive load is not applied to the injection device including the discharge nozzle 42c. The relief valve 43c is connected to the oil pump 42 via an oil passage 43b (see FIG. 2) different from the oil passage 42a.

  Since the relief valve 43c operates at a high speed where the hydraulic pressure supplied to the discharge nozzle 42c by the electric motor 1 is excessive, the oil drain port of the relief valve 43c is connected to the gear shaft of the plurality of stages of the speed reducer 2. Lubricating oil provided at the upper part of the upper gear meshing surface that rotates at the highest speed and dripped from the discharge port of the relief valve 43c is supplied to the gear meshing surface of the upper gear shaft.

  The relief valve 43c is provided in the oil passage 42b between the oil pump 42 and the oil pump 42, and the hydraulic pressure to the injection device of the discharge nozzle 42c is kept constant, whereby the electric motor 1 rotates at a high speed and the discharge amount of the oil pump 42 is reduced. Even when the injection pressure required for the injection device of the oil pump 42 is greatly exceeded, it is possible to protect the injection device such as an injection due to high hydraulic pressure or the injection device from being damaged. Further, when the oil pressure in the oil passage 42b increases, the lubricating oil discharge of the oil pump 42 may be hindered, and a drive loss due to the rotational resistance of the oil pump 42 may occur, but between the oil pump 42 and the oil passage 42b. By inserting a valve that keeps the oil pressure constant, the pump drive loss can be reduced.

  As a scene where the oil pressure rises and the lubricating oil is discharged from the relief valve 43c, there is a case of high speed running (during high rotation of the electric motor 1), but the discharge (dropping) position of the relief valve 43c is the fastest rotating gear. By setting the upper part of the shaft, it is possible to supply the lubricating oil to a portion requiring lubrication in two patterns of low speed rotation and high speed rotation.

  As shown in FIG. 2, the oil pump 42 can be attached from the outside of the side housing 4b of the speed reducer 2 by removing the flow path forming plate 4c fixed to the inner side surface of the side housing 4b of the speed reducer 2. The oil pump 42 having a diameter larger than the outer diameter of the rolling bearing 34 b that supports the intermediate shaft 24 and the rolling bearing 37 b that supports the output shaft 25 can be assembled to the side housing 4 b of the speed reducer 2.

  As shown in FIG. 5, the oil pump 42 includes an inner rotor 72 that rotates using the output rotation of the speed reducer 2, an outer rotor 73 that rotates following the rotation of the inner rotor 72, a pump chamber 74, The cycloid pump includes a suction port 75 that communicates with an oil passage 42a of the oil pump and a discharge port 76 that communicates with oil passages 42b and 43b formed in a flow path forming plate 4c of the speed reducer 2.

  Inner rotor 72 has a tooth profile formed of a cycloid curve on the outer diameter surface. Specifically, the shape of the tooth tip portion 72a is an epicycloid curve, and the shape of the tooth gap portion 72b is a hypocycloid curve.

  The outer rotor 73 has a tooth profile formed of a cycloid curve on the inner diameter surface. Specifically, the shape of the tooth tip portion 73a is a hypocycloid curve, and the shape of the tooth gap portion 73b is an epicycloid curve. The outer rotor 73 is rotatably supported by a pump case 77a provided on the side housing 4b of the speed reducer 2.

  The inner rotor 72 rotates around the rotation center c1. On the other hand, the outer rotor 73 rotates around a rotation center c2 different from the rotation center c1 of the inner rotor. Further, when the number of teeth of the inner rotor 72 is n, the number of teeth of the outer rotor 73 is (n + 1). In this embodiment, n = 5.

  A plurality of pump chambers 74 are provided in the space between the inner rotor 72 and the outer rotor 73. When the inner rotor 72 rotates using the rotation of the intermediate shaft 24 or the output shaft 25 of the speed reducer 2, the outer rotor 73 rotates in a driven manner. At this time, since the inner rotor 72 and the outer rotor 73 rotate about different rotation centers c1 and c2, respectively, the volume of the pump chamber 74 changes continuously. Thereby, the lubricating oil flowing in from the suction port 75 is pumped from the discharge port 76 to the oil passages 42b and 43b, and the discharge nozzle provided on the upper surface of the speed reducer housing 4 of the speed reducer 2 as shown in FIG. Lubricating oil is discharged from the discharge ports of 42c and the relief valve 43c toward the meshing surface of the gear of the speed reducer 2.

  The oil pump 42 is driven by the rotation of the gear shaft that causes the output of the speed reducer 2 to rotate the wheel forward in the forward direction. The rotation direction of each gear shaft is sprayed as shown by the arrows in FIGS. 3 and 4. It is set in the direction in which the applied lubricating oil is drawn off between the gears without being splashed off.

  Next, in the embodiment shown in FIGS. 7 and 8, the one-way clutch 60 is provided between the oil pump 42 and the drive shaft (intermediate shaft 24). The driving loss due to the drag driving is reduced.

  That is, when a cycloid pump is used as the oil pump 42, the suction / discharge direction is reversed during reverse rotation of the pump, so that the lubricating oil in the oil passage flows backward. During reverse rotation, the oil pump 42 is not driven.

  FIG. 9A shows the power transmission state of the one-way clutch 60, and FIG. 9B shows the power cutoff state of the one-way clutch.

  The one-way clutch shown in FIGS. 9A and 9B is generally called a roller type, and mainly includes an outer ring 61, a roller 62, a spring 63, and a cage 64. The outer peripheral surface of the outer ring 61 is fitted into the inner peripheral surface of the inner rotor 72 of the oil pump, and the outer ring 61 rotates integrally with the inner rotor 72 of the oil pump. A predetermined cam surface is formed on the inner peripheral surface of the outer ring 61. An annular gap is provided between the outer peripheral surface of the drive shaft 65 of the oil pump (the intermediate shaft 24 in the embodiment of FIG. 7) and the inner peripheral surface (cam surface) of the outer ring 61, and there are rollers 62 and springs 63. A plurality of sets are arranged. These are held by the cage 64. Each spring 63 urges each roller 62 to one side in the circumferential direction.

  When the drive shaft 65 of the oil pump attempts to rotate in the clockwise direction with respect to the outer ring 61, the roller 62 advances to the meshing position of the inner peripheral surface (cam surface) of the outer ring 61 by the spring force of the spring 63, and The rotation of the pump drive shaft 33c is transmitted to the outer ring 61 by the wedge action between the inner peripheral surface (cam surface) and the roller 62, and the inner rotor 72 of the oil pump rotates.

  Conversely, when the oil pump drive shaft 65 rotates counterclockwise with respect to the outer ring 61, the oil pump drive shaft 65 rotates relative to the outer ring 61, and the roller 62 The outer ring 61 is separated from the inner peripheral surface (cam surface) and idles with respect to the drive shaft 65 of the oil pump, the rotational force of the drive shaft 65 of the oil pump is cut off, and the inner rotor 72 of the oil pump does not rotate.

  As described above, the one-way clutch 60 is switched between ON and OFF depending on the rotation direction of the drive shaft 65 of the oil pump, and the rotation of the oil pump is only allowed to rotate in the direction of sucking the lubricating oil from the lubricating oil tank 41. To do.

  In the one-way clutch 60, the cam surface is provided on the inner peripheral surface of the outer ring 61. However, the cam surface is provided on the outer peripheral surface of the drive shaft 65 of the oil pump, and the inner peripheral surface of the outer ring 61 is a cylindrical surface. You may form in. Further, a one-way clutch other than the roller type may be used.

  Next, the vehicle motor drive device A according to the embodiment shown in FIG. 10 has a reduction gear housing 4 that houses two reduction gears 2 in parallel in the left-right direction, and two reduction gear housings 4 on the left and right sides of the reduction gear housing 4. The motor housing 3 of the electric motor 1 is fixedly arranged.

  The left and right electric motors 1 are accommodated in a motor housing 3 as shown in FIG.

  The motor housing 3 includes a cylindrical motor housing body 3a whose outer surface is open, an outer wall 3b that closes the outer surface of the motor housing body 3a, and an inner wall that is separated from the speed reducer 2 inside the motor housing body 3a. 3c. The inner wall 3c of the motor housing body 3a is provided with an opening for drawing out the motor shaft 12a.

  The speed reducer housing 4 that accommodates the two speed reducers 2 provided in parallel in the left and right has a three-piece structure of a central housing 20a and left and right side housings 20b fixed to both side surfaces of the central housing 20a. The left and right side housings 20b are formed in a substantially symmetrical shape.

  By fixing the side surface on the outboard side of the side housing 20b of the speed reducer housing 4 and the inner wall 3c of the motor housing main body 3a of the electric motor 1 with a plurality of bolts 29, two units on the left and right sides of the speed reducer housing 4 are provided. The electric motor 1 is fixedly arranged.

  A partition wall 21 is provided in the center of the center housing 20a. The speed reducer housing 4 is divided into left and right parts by the partition wall 21, and independent left and right accommodation chambers 22 for accommodating the two speed reducers 2 are provided in parallel.

  An oil pump 42 that is driven by the rotation of the intermediate shaft 24 is provided on the partition wall 21 of the central housing 20a.

  The configurations of the left and right electric motors 1 and the two speed reducers 2 in the embodiment shown in FIG. 10 are basically the same as the configuration of the vehicle motor drive device A shown in FIG. A duplicate description is omitted.

  Next, in the vehicle motor drive device A according to the embodiment shown in FIG. 11, the speed reducer housing 4 that houses the two speed reducers 2 in parallel on the left and right sides is provided in the center as in the embodiment of FIG. In this structure, the motor housings 3 of the two electric motors 1 are fixedly arranged on the left and right sides of the machine housing 4.

  In the embodiment shown in FIG. 11, an oil pump 42 driven by the rotation of the intermediate shaft 24 is provided on the partition wall 21 of the central housing 20a.

  A one-way clutch 60 is provided between the oil pump 42 and the drive shaft (intermediate shaft 24), so that the oil pump 42 is idled during vehicle forward drive to reduce drive loss due to drag driving of the pump.

  Next, in the embodiment shown in FIG. 12 and FIG. 13, the injection device (discharge nozzle 42 c) of the oil pump 42 is provided at a position near the meshing surface of the gear on the side surface of the speed reducer housing 4 that houses the speed reducer 2. This is an example.

  The present invention is not limited to the above-described embodiments, and can of course be implemented in various forms without departing from the gist of the present invention. The scope of the present invention is claimed. The equivalent meanings recited in the claims, and all modifications within the scope.

1: Electric motor 2: Reducer 3: Motor housing 3 a: Motor housing body 3 b: Outer wall 3 c: Inner wall 4: Reducer housing 4 a: Motor side housing 4 b: Side housing 4 c: Flow path forming plate 11: Stator 12: Rotor 12a: Motor shaft 13: Seal members 14a, 14b: Rolling bearing 15a: Outer ring member 20a: Central housing 20b: Side housing 21: Partition wall 22: Storage chamber 23: Input shaft 23a: Input gear 24: Intermediate shaft 24a: Large Diameter gear 24b: Small diameter gear 25: Output shaft 25a: Output gears 27a, 27b: Boss portions 28a, 28b: Rolling bearing 29: Bolt 31: Seal members 32, 33: Boss portion 33c: Pump drive shafts 34a, 34b: Rolling bearing 35, 36: Boss portions 37a, 37b: Rolling bearings 39: Seal portions Material 41: Lubricating oil tank 42: Oil pumps 42a, 42b: Oil passage 42c: Discharge nozzle 43b: Oil passage 43c: Relief valve 60: One-way clutch 61: Outer ring 62: Roller 63: Spring 64: Cage 65: Drive shaft 72 : Inner rotor 72a: Tooth tip portion 72b: Tooth groove portion 73: Outer rotor 73a: Tooth tip portion 73b: Tooth groove portion 74: Pump chamber 75: Suction port 76: Discharge port 77a: Pump case 81: Electric vehicle 82: Chassis 83: front wheel 84: rear wheel 86: constant velocity joint 88: intermediate shaft A: vehicle motor drive device

Claims (6)

  An electric motor for generating a driving force; a speed reducer that decelerates and outputs the rotation of the electric motor by a plurality of stages of gear shafts; a housing that houses the speed reducer; a lubricating oil tank provided in the housing; An oil pump that is driven by the rotational power of one of the gear shafts of the stage, sucks the lubricating oil from the lubricating oil tank, and supplies the lubricating oil to the gear tooth surface of the speed reducer via the injection device In the vehicle motor drive device for driving a wheel by the output of the speed reducer, the oil pump is set to obtain a hydraulic pressure required for the injection device at a rotational speed lower than the maximum rotational speed of the electric motor. A vehicle motor drive device, wherein a relief valve for preventing excessive hydraulic pressure is provided in an oil passage between the oil pump and the oil pump.   The oil relief port of the relief valve is provided at the upper part of the upper gear meshing surface of the gear shafts of the reduction gears, and the lubricant dripping from the relief valve exhaust port is applied to the gear meshing surface of the gear gear upper stage. The vehicle motor drive device according to claim 1, wherein the vehicle motor drive device is supplied.   A housing that houses two speed reducers in parallel in the left and right is provided in the center, two electric motors are provided on the left and right sides of the housing, and the two speed reducers provided in the left and right parallel to the housing of the central speed reducer The vehicle motor drive device according to claim 1, wherein a common oil pump is provided.   The vehicle motor drive device according to claim 1, wherein an oil pump injection device is provided on a side surface of the housing that houses the speed reducer.   2. A lubricating oil tank is provided at the bottom of a housing that houses the speed reducer, and the oil level of the lubricating oil tank is located below a tooth surface of a gear provided on a plurality of gear shafts constituting the speed reducer. The motor drive device for vehicles in any one of -4.   6. The vehicle motor drive device according to claim 1, wherein the oil pump is a cycloid pump.

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